Tying machine



Dec. 12, 1939. B. H. BUNN 2,132,959

- Mme IIAOHINE Filed July 16, 1957 s Sheets-Sheet 1 Dec. 12, 1939. B.v H. BUNN TYING MACHINE Filed July 16, 1937 B. H. BUNN MING IACHINE 7 Filed July 16, 1937 Dec. 12, @939.

3 Sheets-Sheet 3' 3 J79 Jag 2'20 I 9-25 figd'mwfl 15am 71% i atentedi time. 12, E939 PA em ()FFICE 'E'YING MACHINE Benjamin H. Bunn, Chicago, 111., assignmto' B. H. BunnmCompany, Chicago, Iil.,'a corporation of Application July 16, 1937, Serial No. 153,940

11 Claims.

My invention relates to tying machines and especially to that type of tying machine which puts one or more wraps of twine about a package and then ties a knot in the ends of the twine.

In general my present invention is concerned with certain improvements in the details of the tying machines shown in my prior Patents No. 1 606,290 of November 9, 1926, and No. 1,994,453 of March 19, 1935. Among these improvements are the following:

(a) Better insurance against the knotted portion of the twine slipping past the stripper as the knot loop is stripped from the beak or knotting head on which it has been formed;

(1)) Better adaptation of the jaws of the beak to handle varying sizes of twine in pulling out the loop as the knot is formed, and the disposition of the double reaches of twine between the jaws to facilitate a more advantageous and reliable engagement-by the stripper; and

(0) An improved conformation for the crown of the upper jaw of the, knotter beak which is calculated to help the twine passing thereover" to work itself toward the point of the jaws.

- The foregoing, together with further objects, features and advantages of my invention, are set forth in the following description of a specific embodiment thereof and illustrated in the accompanying drawings. The description and drawings are intended primarily to disclose my present improvements over the disclosures of my previously mentioned prior patents, and the reader is referred to those prior patents for a more complete disclosure of the nature and operationof the parts shown and for the mechanism by which the parts shown are mounted and operated in properly timed sequence. Also, for a more convenient reference back to my prior patents, I have here employed the same reference characters as are used in the prior patents to identify the same, or corresponding, parts. To avoid confusion because of this use of the reference char- No. 1,606,290. The disclosure of my Patent No.

1,994,453 differs from that of my Patent No. 1,606,290 chiefly in the elimination'of the packsame number in my prior age positioning guides and package clamp, and in the modification of the wrapping arm drive mechanism whereby the wrapping arm puts one wrap of twine about the package and then pauses until the operator actuates a foot pedal to resume the wrapping whereby the wrapping arm forms a second wrap, the end of which'is caught in the twine catcher. performed in accordance with my Patent No. 1,606,290. The purpose of the pause between the first and second wrappings is to permit the operator to turn the package through 90 so that one wrap is longitudinal and one wrap is transverse. if desired, however, the wraps may be parallel and together, in which case the package is not turned during the pause. I contemplate, as set forth in my Patent No. 1,994,453, that provision may be made for more than two wraps.

Many aspects of my present invention are not confined to a multi-wrap tying machine, but

some of them are particularly advantageous where a. plurality of wraps is employed and therefore I have here illustrated an embodiment of my invention where two wraps are employed, one longitudinally of the package and one trans versely thereof.

In the drawings:

Fig. l is an elevation of the knotting mechanism and associated parts. corresponding with Fig. 5 of my Patent No. 1,994,453 (and in turn corresponding with Fig. 8 of my Patent No. 1,606,290) except that less of the operating mechanism for the knotter is shown, and except that the parts are shown in the position they oc-' cupy at a later stage in the formation of the knot-a stage immediately before that of Fig. 16

of my Patent No. 1,606,290. 1

Fig. 2 is a somewhat diagrammatic perspective view showing in phantom the package being wrapped and showing the two wraps of twine in place on the phantom package and with the parts in the position or stage'immediately following that of .Flg. 1. In this figure the parts are viewed from the same side as in Fig. 1 but partly from above and from the left.

Fig. 3 is a perspective view similar to Fig. 2

but at an earlier stage in the cycle of operation,

namely, as the third side of the second wrap is being formed and just before the twine of the third wrap is caught in the twine catcher to anchor the other end as well during the tying operation.- In this figure, as well as in Fig. 2, many of the parts shown in ,Fig. 1 are omitted for clarity or indicated only in broken lines.

4 is an elevation of the knotter, partly in Then the knotting operation is 2 aieaeee section, taken on the line 8-4 of Fig. 1 and showing the knotter in the position of Fig. 2.

Fig. 5 is a perspective view of the tip-up arm,

or twine lifting lever, corresponding to Fig. 34 of 5 my Patent No. 1,606,290.

Fig. 6 is a plan section taken on the line 6-6 of Fig. 1 showing the twine catcher and its mounting but with the twine removed.

Fig. 7 is a plan view of the knotter head as it is being moved backwardly and the knot stripped from its beak by the strippers and showing in plan the'parts of Fig. 4 at a later stage.

Fig. 8 is a perspective view of the horizontally pivoted stripper which engages the right (Fig. 1)

side of the knotter beak.

Fig. 9 is a front end elevation of the stripper of Fig. 8, and

Figs. 10a to 10c, inclusive, are views of the various sides of the twine catcher block as viewed 99 from the front (Fig. 1), the top, the right (Fig. 1) side, the bottom, and the left (Fig. 1) side of the block. The purpose of this set of figures is to show the contour of the front face of the block against which the back, or shoulder, of the twine g5 catcher button cooperates in holding the twine.

The package P to be wrapped is here shown as of rectangular box-like form but it may be of other form or in the nature of a bundle or of a stack of sheets, such as labels or the like, whether sheet wrapped or not. The package is set upon a table 84 suitably mounted on the general frame Bil of the machine, with one side of the package against the shoulder formed by the normal downward flexing of the forward edge of the right (Fig. 1) hand portion 880 of the table. The end TI of the twine T is caught between the head or button I23 and the block I29 of the twine catcher (Fig. 3). By its first clockwise rotation, as indi-= cated by the arrow in Fig. 8, the wrapping arm. @9 92 has passed around all four sides of the package P while the package was disposed at 90 to the position shown in Fig. 3. Thereby the first wrap T2 has been laid longitudinally about the package. Following the first wrap T2, and as set 5 forth in detail in my Patent No. 1,994,453, rotation of the wrapping arm IE2 is suspended while the operator has turned the package through 90 to the position of Fig. 5 and until the operator has pressed a control pedal to resume the wrapping operation. Thereupon the wrapping arm 92 commences a second rotation which forms the second wrap 'rs. In the position of Fig. 3 the twine may be traced as follows:

The end TI is caught in the twine catcher between the head I28 and the front face of the block I20. From there a reach of twine TE extends to the concatenation T5 and thence longitudinally around the package as the first wrap T2, back to the concatenation T5 and then across 50 onehalf of the bottom, upwardly along the adja cent side, and across the top to form part of the second wrap T3. In Fig. 3 the wrapping arm 82 has completed about three-quarters of its second wrapping revolution and the twine extends di- |5 rectly from the top reach of the second wrap T3 obliquely downwardly to the tip guide of the wrapping arm 82, as indicated at T6.

The twine catcher is disposed substantially in the vertical plane in which the tip of the wrap- 0 pins arm 92 rotates.

wrapping arm 92 has rotated a few degrees beyond the position of Fig. 3, the reach T6 of the twine will engage the twine catcher and be caught in the space between the rear face of the head I23 5 and the front face of the b k I 20.

For this reason, after the At this point I wish to describe the mechanism which prevents the'reach of twine extending from the package to the wrapping arm from being caught by the twine catcher during the first wrap but which insures its being caught in the second 5 wrap. as Just described.

A plate I32 is mounted on the main frame of the machine for horizontal reciprocation a spaced distance below the table 85. That portion of the plate I32 which underlies the table is guided 10 by a pair of tandem slots A25 and A26 into which. extend studs or pins A21 fixedly carried by the main frame. This provides a generally rectilinear path for reciprocatory movement of the plate I82. One end of the plate I32 carries a 15 U-shaped projection I35. The imam end A26 of the slot A28 is oflset slightly from the center line of the main body of the slot A26 and of the slot A27. Thus the reciprocation of the plate I22 and consequently of the free end of the U- 2% shaped projection I35 is strictly. rectilinear, unless and until the plate is. slid so that the pins A2? come to the far end of their slots. In'that case one of the pins enters the offset slot portion A26 and moves the free end of the projection I35 later- 95 ally away from the reader.

'Reciprocation of the plate I32 is effected by one arm of a bell crank I21 pivoted at I28 to a bracket carried by the machine frame. The free end of the arm engages a bifurcated or slotted 861 boss #88 which depends from the plate E32. At the proper times in the cycle of the machine, the cam which rocks the bell crank I2? causes the plate [22 to be reciprocated to its several positions.

when the wrapping arm passes its position of Fig. 3, but on the first wrap, the bell crank holds the plate 552 in a position where the pin A27. is in the main body of the slot A26 but near the inner end thereof. In that position the free end of the projection I35 is nearer the reader and its outer edge serves as a guide to carry the oblique reach of twine past the twine catcher 923. But when the wrapping arm 92 reaches the position of Fig. 3 on its second wrap, the bell crank i2: has shifted the plate I32 so that the pins AZ? come at the inner ends oi their slots, including the ofiset portion A28. This produces a lateral shifting about the rearward pin A27 so that the outer face of the free end of the projection E35 50 is ofiset from the plane of the twine catcher I23 and permits the oblique reach of twine to be engaged thereby. Continued movement of the wrapping arm to the completion of the second wrap, as shown in Figs. 1 and 2, leaves the final 55 reach of twine engaged by the twine catcher along with the initial end TI.

This lateral shifting of the projection I35 for better insuring the passing or engagement of the twine catcher by the twine during the wrap- 69 ping operations, is one of the features of my present invention. According to my two earlier patents mentioned, the plate I82 had only a simple rectilinear movement, and the twine was caused to engage the twine catcher I23 in the 55 last wrap-the wrap which immediately precedes the tyingby merely withdrawing the free end of the extension I35 by the rectilinear movement of the plate I32, leaving a gap or space between the free end thereof and the twine catcher into 70 which the oblique reach of twine would snap under tension. This was because the edge face of the extension I 35 was in a plane slightly toward the reader from the plane of the twine catcher I23, By my prment invention that gap is still provided, but in addition the offset end of the slot A26 causes a lateral shifting away from the reader as theoblique rmch of twine passes toward the twine catcher in' the last wrap.

- The edge face of the extension Ill is thereby and at that time shifted into the plane of the abutment of the twine catcher button with the block I 29, and the twine is not required to snap under brought to rest in its normal position of Fig. 2,

the slide is moved to the right from the position shown in Fig. 3. As the pin All slides out of the offset portion A29 into the main bodyof the slot A26, the free end of the U-shaped pro- Jection I95 is shifted toward the reader to its normal plane, and it is then brought to the right so that the V-shaped end edge thereof engages the reach of twine T6 and also the first reach tated at the proper time.

iournaling boss I I5 is carried at the upper end iii) iii

of twine T8 and carries them beneath the beak of the knotter head. That is the position shown in Fig. 12 of my Patent 1,606,290. The knotter head is carried on the upper end of a knotter shaft I51 (Fig. 4) and comprises a member I58 carrying integrally therewith an upper jaw I59 with a lower jaw I pivotally mounted on the member I58 to cooperate with the upper jaw. The lower jaw I69 is hell crank in form, and its lower oflset arm carries a roller I8I which en-= gages an annular cam face I" provided at the upper end of the boss I55 in'which the knotter shaft IE1 is journaled The lower end of the shaft I 51 carries a pair of bevel gears I68 and 39 (Fig. 1) by which the knotter head is ro- The knotter shaft of a knotter bracketing member I48 which is pivotally mounted on a transverse pin 9 on a bracket I29 depending from the main frame. The lower end of the member I48 comprises an arm I59, at the bottom of which is a roller (not shown) engaged by a cam for rocking the entire member I48 about the shaft I49 to pull the knotter'head rearwardly or push it forwardly as required. The reader is referred tomy Patent 1,606,290 for further details of the mounting and operating mechanism for the knotter bracketing element i623. r

Inthe position of Fig. 3, the knotter head is in its normal rearward position behind the plane of the wrap. After the last wrap oi twine is caught in the twine catcher I28 and the plate iii starts to slide to the right to the position of Fig. 2, the bracketing element I88 is rocked to bring the knotterhead forwardly with its beak projecting through the plane of the last wrap.

Thus by the time the plate 2 reaches its rightmost position, the free end of the projection 6th is beneath the beak of the mutter. The sliding plate 982, as just described. W11. the two reaches 'l i and we of the twine to the right of the knotter beak, as shown in Fig. The tip-up lever use now engages the first reach of twine T6 and lifts it upwardly so that a portion of thatreach will lie along the righthand side of the knotter beak, so that when the knotter beak turns counterclockwise both reaches of twine will be wrapped about the beak. The

' is more positively engaged by the projecting porand structure involved up to the position of Fig. 2,

lihk I9I is pivoted to the lever I89 and the other 7? end to a pin (not shown) carried by the knotter bracketing frame I88. The reader is referred to my prior Patent 1,606,290 for further details of the operating mechanism for the tip-up lever N39. Sufiice'it to say that the link i9i serves to as the lever I89 upwardly when the knotter beak is rocked forwardly about the pivoting pin hit for the bracketing frame M8.

The tip-up lever its carries a transverse slot I90 which engages the reach of twine Til and moves it upwardly to the position of Fig. I (ahthough in the position of Fig. 1 the knotter head has rotated through a complete revolution to wrap the two reaches of twine about the beak).

A comparison of Fig. 5 with Fig. 3d of my prior Patent 1,606,290 will best show the improvement I have madein the tip-up lever ltd. Previously the slot I98 was so formed that the upper and lower walls of the slot were of equal depth and the tension of the reach of twine was relied upon Q to cause the twine to snap into the slot ltd in order that it be properly engaged. By my present invention I build up the height of the lower wall of the slot I89, as indicated at A28, so that it projects outwardly beyond the margin of the upper wall. In this way the reach of twine Td tion A28 at the lower wall. of the slot i9d instead of relying wholly on the tension of the reach of twine to snap it into the slot I99. This constitutes another feature of the present invention.

I have now described the cycle of operation which shows the reach of twine T4 pulled upwardly along the right side of the knottei' beak as the result of the lifting action of the tip-up lever I89. The next step is the rotation of the knotter head. Means for eil'ecting the rotation. beyond the bevel gears I68 and see, is not here illustrated and I refer the reader to my prior Patent 1,606,290 for further disclosure.

The knotter head rotates counterclockwise, when viewed from above. As the knotter head starts to rotate from the position shown in Fig. 2,

the reaches of twine T5 and T4! are engaged by I the advancing side of the beak. By the time the knotter has made half of its revolution-that is.

by the time its beak points rearwardly--the reaches of twine Ti and T6 are wrap side by side a full turn about the knotter heals. As e knotter head rotates from its half revolution po= sition to its three-quarter revolution position,

the roller IN on the lower jaw ltd of the knotter beak rides up onto the protruding or eccentric portion of the cam surface are, causing the jaws of the beak to open and receive the two substan= tially parallel reaches of twine. .After this, all

This brings the cycle immediately subsequent to the position of Fig. i. Fig. 1 she the lower law oi the knotter beak still dropped. lrnme= dlately following that position, the roller iiii will drop to close the lower jaw the at the end of the complete revolution of the knotter head. The sliding plate 632 has been withdrawn after the 4 a,1ea,ose

first quarter of revolution of the knotter head. The tip-up lever I is still in elevated position, but its function is no longer required and it will he turned downwardly when the knotter beak is drawn rearwardly to its normal position.

The next step in the knotting operation is to pull that portion of the two reaches of twine which are grasped within the knotter beak, back= wardly through the portions of twine which encircle the knotter beak externally, to form the characteristic loop 01' a twine knot. To do this the knotter beak is withdrawn backwardly while the twine, which encircles the beak externally, is held against going backwardly with the knotter beak, and hence the knotter beak is pulled out from the encircling twine as the beak pulls some of the twine through the encircling twine to form the loop of double twine.

This rearward withdrawal of the knotter beak is efiected by rocking its bracketing member I48 about its pivotal mounting I 4! on the main frame. The twine which externally encircles the knotter beak is precluded from backward movement along with the beak by a stripper I" which engages the right side of the knotter beak to strip the encircling twine therefrom as the knotter beak moves backwardly. In my Patent No. 1,606,290 I show additionally an auxiliary stripper for the left side 01 the beak. It is not shown here because I ilnd that with my present improvements the auxiliary stripper may safely be omitted in most installations.

The stripping means which engages the righthand (Figs. 1, 2 and 3) side of the knotter beak comprises a generally horizontal stripper plate I38 carried beneath the table He and illustrated per se in Figs. 8 and 9. By means of a depending lateral flange it is pivoted about a transverse horizontal axis to the main frame of the machine. Its forward end is turned downwardly to form a lip I39, at the left-hand edge of which is a slot I40. The left-hand edge of the lip I is adapted to engage the right-hand face of the knotter beak as the knotter beak is moved rearwardly, thereby stripping the encircling twine from the beak. The slot I is or a size calculated to accommodate two side by side portions oi twine. Specifically, these are the two portions of twine which emerge to the right from the interior of the jaw which is grasping the two side by side portions of twine which it has previously received. As the encircling twine is stripped from the beak, these two emerging portions of twine, which will ultimately form the loop of the knot, are progressively leit lying along the right-hand side of the rearwardly moving beak. The purpose of the slot I40 is to accommodate these portions 01' twine so that the stripping lip I" will not cut them.

The improvement which I have made by my present invention in the stripping plate I is the provision of a milled counterslot A29 in the forward face of the lip I38, so arranged that it forms an acute angle for the stripping edge AM of the lip I39. This acute angled stripping edge A80 is better calculated to engage and strip the encircling twine from the knotter beak. Previously. with a zight ongled stripping edge, there was more tendency for the stripping plate to ride over the encircling twine on occasion without properly stripping it. The acute angled stripping edge tends to wedge itself between the right-hand face of the knotter heel; and the twine and preclude danger of the shipper riding over the twine and telling to strip It will beunderstood that the stripper I" is normally out of position so that it does not interfere with the rotation of the knotter head, but

after the knotter head has completed its rotation it is brought into stripping position during the backward withdrawal oi the knotter beak.

The adJacent ends of the two reaches of twine 'rs and T4, being caught side by side in the twine catcher. I23, are anchored during the tying operation. As previously stated, the parallel portions of twine,'whlch are gasped in the laws or the knotter beak, are pulled through the pair of encircling portions of twine which have been wrapped about the knotter beak. The other ends of the reaches of twine T4 and TI are held by the package and by the concatenation TI. The length of twine which is pulled backwardly by the knotter beak to form the loop of the knot, comes from the length of the beak-encircling twine. In other words, the side by side knot loops which are pulled out by the knotter beak are formed, for the most part, of twine which was originally in the encircling portions of twine which become of progressively less circumference as the encircling twine is stripped toward the tapered or pointed end of the beak as the knotter head is drawn backwardly.

I shall describe the completion of the knottlng operation and then revert. to a discussion of an improvement I have made in the knotter beak.

As the encircling twine is strlpped oi! the point of the beak and the knot loops are formed by the backward movement of the knotter beak. a cutter carrier I'll, which is pivotally mounted on a suitable bracket carried by the main frame, is swung outwardly and downwardly so that its groove or notch I85 engages the initial reach of twine T4 and moves it downwardly so that it will not be cut bythe cutter blade I" borne by the carrier I'll. The outter blade I", however. will cut the reach of twine T6 a short distance to the right of its anchorage on the-twine catcher I23. That leaves thetwine extending from the end of the wrapping arm to the twine catcher but severed shortly therebeyond, so that that portion of the twine is ready for the next cycle 01' operation. The continued downward swinging of the cutter carrier notch or groove Ill pulls the original reach of twine T4 loose from its anchorage on the twine catcher I23 against its trictional retention thereby. This frees the knot entirely from anchorage on the machine. and the wrapped and tied package P may then be removed, leaving the machine tree for the next cycle oi operation upon another package.

Having now completed a description of a complete cycle of operation and the pertinent structure involved, I shall return to a description of the improvements I have made by the present invention in the knotter head. One improvement consists in shifting the crown All 02 the knotter head to the rearward side of the axis of the knotter shaft I61, as best shown in Fig. 4. With the crown or highest point on the knotter head placed at the side of the axis opposite from the point of the beak, I am better assured that the pair oi beak encircling portions of twine will he urged toward the point of the beak when they are tightened. Previously the crown of the head has been on the side of the axis toward the beak and on occasion the encircling twine has lodged in the region of the axis and behind the crown and has not prom-em. arly toward the point of the beak, seems s so would have to ride up over crews...

Another improvement in the knotter head consists in the conformation of that portion of the beak which receives the side by side portions of twine which are to be pulled through the encircling twine to form the knot loops. Still referring to Fig. 4, the underside of the upper jaw I59 is fiat and horizontal. The top face of the lower jaw I60 is cut out to provide a shoulder A32 and a horizontal ledge A33 parallel with the under face of the upper jaw I59 and spaced therefrom by a distance slightly less than'the minimum diameter of twine which will be employed and extending rearwardly (to the left, Fig. 4) from the shoulder A32. The ledge A33 extends horizontally and parallel with the underface of the upper jaw I59 for a distance rearwardly of theshoulder A32, which distance is a little morethan two twine diameters. Rearwardly of that the ledge is inclined as shown at A34. The free end of a leaf spring I62 engages the roller IBI on the depending arm of the lower jaw I60 yieldingly to close the lower jaw against the upper jaw. When the jaws are opened, as previously explained, in the course of a revolution of the knotter head, the two side by side portions of twine are received therein near the bight of the open jaw, so that when the lower jaw I60 is again closed the portions of twine engaged by the jaw lie close to the bight and against the encircling twine, as shown in Fig. 4. However, the inclined face A34 of the jaw I60 afiords suflicient clearance at that region so that the portions of twine engaged within the jaw may readily move outwardly toward the the region of the ledge A33 in side by side relation and against the shoulder A32. This conformation of the mating surfaces of the upper and lower jaws I59 and I60 better adapts the knotter head to different sizes of twine.

Another feature of my present invention is concerned with the mounting of the twine catcher I23 on its block I and the conformation of the cooperating juxtaposed surfaces of the button of the twine catcher and of the block 120;

The button or the twine catcher iii is beveled or frusto-conical at its peripheral edge A35. The inner face A33 of the button of the twine catcher forms a but-slightly rounded corner with the tapered edge A35. The stem I2I is received within an inner bearing A31 and an outer bearing A38. The inner bearing 'A3Ifits the stem 7 reasonably closely, but the outer bearing A33 is quite loose to permit considerable oscillation of the stem. A spring I22, interposed between the rear face of the block I20 and a lock nut on the stem, urges the inner face A35 of the twine catcher button against the front face A39 of the block.

The conformation of the face A39 is one of the features of my present invention. The face A39 is somewhat spiral so that it represents approximately a convolution of a helix with a small axial advance. This helix starts at an approximately radial shoulder A40 and extends counterclockwise (Fig. 101:) with a gradual outward may be from either or both of two causes.

r pens to be.

. (toward the reader) progression back to the shoulder A40. The height of the shoulder A40 is somewhat less than the minimum diameter 01 twine to be employed. As a result of this helical conformation of the face A39, it appears in the plan view of Fig. 10b to be inclined. The corner of the block opposite the shoulder AM! is generously rounded ofi and the two intermediate corners are rounded off to a lesser degree.

The shoulder A40 comes at the upper righthand (Figs. 1, 2 and 3) corner of the block, that is, at the upper corner of the block toward the knotter head. The resulting somewhat oblique disposition of the face A39, as best shown in the drawing of Fig. 10b and the bottom view of Fig. 10d, tends to urge the stem l2I of the twine catcher toward the left-hand side of its bearing A31. The highestor more properly the outermostregion of the face A39, as it is engaged by the button face A36, is toward the'right of the stem, that is, toward the knotter. Consequently, twine caught by the twine catcher is engaged more tightly on the right side of the face A39. I

This feature is of peculiar advantage. The original reach of twine T4, as well as the reach T6, are yieldingly held by the twine catcher. Under sufficient tension some additional length of twine can be, and generally is, pulled from the twine catcher. This additional pulling out One is the tension of the two reaches T4 and T6 as they are carried to the right and beneath the knotter beak by the free end of the U-shaped projection I35 of the sliding plate I32. The other is the tension created by the revolution of the knotter beak to encircle itselfby the two reaches of twine. Both of these tension actions result from the necessity of increased lengths of twine for the two reaches. The increased length may come from either or both of two sources. It may come frompulling some more twine through the twine catcher. Or, it may come from the twine wraps, by pulling them tighter.- How .much will, come from the latter source-the wraps-depends on how soft or compressible the bundle or package is in relation to how tightly the twine is held by the twine catcher. The bundles or packages will vary in softness or compressibility. Sometimes the additional twine will come wholly from the wraps, sometimes wholly from the twine catcher, sometimes partly from each.

Thus the shorttail TI by which the reach T4 of twine is anchored to the twine catcher will be partially pulled through the twine catcher to a variable or unpredetermined extent. In some instances the anchoring tail Tl of the twine may be pulled so far that it is held only by its very,

end at the right-hand side of the twine catcherthe side from which it emerges. If the twine catcher. held'tighter on the left side than on the right side, the twine end would not be held suiiiciently tightly during the knotting operation; But by my present invention the face A39 is so contoured, and the button I23 is so mounted, that the twine is held most tightly on the right side. Thereforepduring' the lmottin-g operation. the reach T4 of twine is held adequately and with uniform tension no matter how short the anchoring tail TI left in the twine catcher hap This makes the anchorage and release forthe reach T4 of twine more positive and satisfactory and does not tend to dislodge the anchorage for the new reach of twine which extends between the twine catcher and free end of the wrapping arm 92.

The reach of twine T6 in extending from. the twine catcher to the knotter head passes from the top side of the twine catcher and lies along the shoulder A40. The shoulder A40 thus serves as an abutment better to hold up the twine catcher end of the twine reach T6 so that it will be severed by the cutter and kept spaced sufilciently above the original reach of twine T4 so that it will not be engaged by the groove I along with the reach T4. The inclination of the face A39 is such as to discourage the button being tilted toward the free end of the extension I35 of the sliding plate I32, so that the free end thereof may come just above the button of the twine catcher in moving the twine under the knotter beak, but still avoid danger of the twine catcher button binding against the bottom face of the extension I35.

If the bearing for the stem did not permit any oscillation and the front face A39 of the block I20 were fiat rather than somewhat helically conformed, the tension of the twine holder on the twine and its adaptability to difierent sizes of twine would depend solely on the axial outward movement of the stem I2I against the pressure of the spring I22. That would tend to cause self-camming action on the twine. By

providing the front face of the block A39 with the contour as shown and providing for oscillation of the outer end of the stem I2I, the tightening of the twine between the button and the face A39 tends to pull the stem I2I, within its oversize bearing A39, to the right, that is, toward the twine catcher. As a result the twine catcher will hold different diameters of twine with a fairly uniform tension and without the necessity of adjusting the tension of the spring I22, by

, resetting the lock nuts, to adapt it to different diameters of twine.

I prefer to drill a vertical hole A4I through the block I 20 to intersect the bearing A38. The purpose of the hole All is to provide an exit for those pieces of lint which come loose from the twine as the twine is pulled through the twine catcher and work themselves into the bearing A38. If these pieces of lint are permitted to accumulate in the bearing A38, they would eventually clog it and render the twine catcher unsatisfactory in operation.

While I have shown and described these specific embodiments of my present invention, I contemplate that changes and substitutions may be made thereover without departing from the scope or spirit of my invention.

Certain of the improvements disclosed herein-for example, the improved mounting of the twine catcher, the improved tip-up arm, and the improved draw slide-are the subject-matter of my application, Serial No. 281,197, filed June 26, 1939, which is a division hereof.

1. A tying machine comprising in combination, a knotter having a beak for receiving a double wrap of twine thereabout and grasping an in-- tegral extension of the twine between the jaws to pull it through the beak-encircling twine to form a knot loop, the beak having two jaws mounted for relative articulation, and a stripper cooperating with the beak along one side thereof by relative motion of the stripper and beak longitudinally of the beak to strip the encircling twine therefrom, the stripper comprising a portion extending laterally toward the side of the beak and presenting an edge thereadjacent, a notch in the edge for receiving the side by side reaches of twine being pulled through the encircling twine, the face of the said portion of the stripper toward the point of the beak being disposed at an angle to the side of the beak whereby the stripping edge presents an acute angle corner.

2. A tying machine comprising in combination, a. knotter having a beak for receiving a double wrap of twine thereabout and grasping an integral extension of the twine between the jaws to pull it through the beak-encircling twine to form a knot loop, the beak having two jaws mounted for relative articulation, and a stripper cooperating with the beak along one side thereof by relative motion of the stripper and beak longitudinally of the beak to strip the encircling twine therefrom, the stripper comprising a portion disposed substantially in a plane at a normal to the axis of the stripper and having a stripping edge lying adjacent the side of the beak, and a slot in the face of the said portion toward the point of the beak for conforming the face corner of the stripping edge to an acute angle corner for the purpose described.

3. A tying machine comprising a knotter having a beak for receiving parallel reaches of twine encircling the beak in a plane transverse there- .of, the beak comprising jaws for receiving integral extensions of the encircling twine to pull the extensions through the encircling twine to form knot loops, and a stripper mounted to ride along one side of the beak to strip the encircling twine therefrom, the stripper having a stripping edge forming an acute angle.

4. A tying machine comprising a knotter having a beak for receiving parallel reaches of twine encircling the beak in a plane transverse thereof, the beak comprising jaws for receiving integral extensions of the encircling twine to pull the extensions through the encircling twine to form knot loops, and a stripper mounted to ride along one side of the beak to strip the encircling twine therefrom, the stripper having a stripping edge forming an acute angle, and a notch in the stripping edge for receiving the loop-forming reaches of twine at the side of the beak.

5. A tying machine comprising a knotter having a beak for receiving parallel reaches of twine encircling the beak in a transverse plane, the beak having a pair of jaws for receiving integral extensions of the encircling twine to draw them through the encircling twine to form knot loops, one of the jaws being articulably mounted upon the other, one of the jaw faces being fiat and the cooperating jaw face having a portion adjacent the point adapted to close upon the first face, a shoulder at the end of said portion, a ledge extending rearwardly of the shoulder parallel with and a spaced distance from the first face, and continuing into an inclined portion extending rearwardly of the beak point and away from the first face. A

6. A tying machine comprising a knotter having a beak for receiving parallel reaches of twine encircling the beak in a transverse plane, the beak having a pair of jaws for receiving integral extensions of the encircling twine to draw them through the encircling twine to form knot loops, one of the jaws being articulably mounted upon the other, the first jaw face being flat and the cooperating jaw face having a first portion adjacent the point of the beak for closing flush against the first face, a second portion rearwardly beak having a pair of jaws. one of which is arthereof and spaced therefrom by a distance slightly less than the diameter of the'twine, and forming a shoulder-at the junction of the first and second portions, and a third portion extending rearwardly from the second portion and inclined away from-the first face.

7. A tying machine comprising a knotter having a beak for receiving parallel reaches of twine encircling the beak in a transverse plane, the beak having a pairof jaws, one of which is articulably mounted upon the other with their cooperating faces receiving extensions of the encircling twine to draw them through the encircling twine to form knot loops, the first jaw face being flat and the cooperating jaw face having a first portion adjacent the point of the beak for closing flush against the first face, a second portion rearwardly thereofand spaced therefrom by a distance slightly less than the di-' ameter ofthe twine, and forming a shoulder at the junction of the first and second portions, and

a third portion extending rearwardly from the second portion and inclined awayfrom the first face, the length of the second portion being in the order of twice the diameter of the twine.

8. A tying machine comprising a knotter having a beak forreceiving parallel reaches of twine encircling the beak in a transverse plane, the beak having a pair of jaws, one of which is articulably mounted upon the other with their cooperating faces receiving extensions of the encircling twine to draw them through the encircling twine to form knot loops, the cooperatin jaw faces being so conformed relative to-each other as to provide a portion adjacent the beak point where the faces may come together, a second portion rearwardly of the first portion and separated therefrom by a shoulder, the faces being spaced apart at the second portion by a space slightly lea than the diameter of the twine, the second portion being of a length in the order portion of wedge shape extending rearwardly from'the second portion and of increasing space toward the bight of the laws. I

.9. A tying machine comprising a knotter havin a beak. for receiving parallel reaches of twine cncirclingthebeakinatransveraeplanathe ond portion rearwardly of the first portion and separated therefrom by a shoulder, the faces being spaced apart at the second portion by a space slightly less than the diameter of the twine,

and a third portion of wedge shape extending rearwardlyfrom' the second portion and of increasing space toward the bight of the jaws.

10. A tying machine comprising a knotter head having a beak extending therefrom for receiving parallel reaches of twine encircling the beak, a bearing for jo'urnaling the head for rotation about an axis substantially at right angles to the beak and spaced rearwardly from the point of the beak, the beak comprising cooperating jaws adapted to receive continuations of the encircling reaches for pulling them through the encircling reachesto form knot loops, and a stripper for relative movement along the beak toward the point thereof for stripping the encircling twine from the beak, theend of the beak remote from its point having .a crown portion with the high point of the crown on the side of the axis opposite the point of the beak.

11. A tying machine comprising a knotter head, means for journaling the knotter head for rotation, a beak extending from the knotter head substantially at right angles to the axis of rotation tension tends to move toward the point.

1 BENJAMIN H. BUNN. 

